Introduction

Sampling Techniques and Statistical Inference

Introduction

Pandurang Vasudeo Sukhatme (1911–1997) was an award-winning Indian statistician. He is known for his pioneering work of applying random sampling methods in agricultural statistics and in biometry, in the 1940s. He was also influential in the establishment of the Indian Agricultural Statistics Research Institute. As a part of his work at the Food and Agriculture Organization in Rome, he developed statistical models for assessing the dimensions of hunger and future food supplies for the world. He also developed size and methods for measuring the  nature of the protein gap.

In any statistical investigation, the interest lies in the assessment of one or more characteristics relating to the individuals belonging to a group. When all the individuals present in the study are investigated, it is called complete enumeration, but in practice, it is very difficult to investigate all the individuals present in the study. So the technique of sampling is done which states that a part of the individuals are selected for the study and the assessment is made from the selected group of individuals. For example

(i) A housewife tastes a spoonful whatever she cooks to check whether it tastes good or not.

(ii) A few drops of our blood are tested to check about the presence or absence of a disease.

(iii) A grain merchant takes out a handful of grains to get an idea about the quality of the whole consignment.

These are typical examples where decision making is done on the basis of sample information. So sampling is the process of choosing a representative sample from a given population.